Coupling arrangement in power steering for vehicles

Abstract

A power-assisted steering device for automotive vehicles having a power-assisted steering valve provided with a rotor, with a tubular sleeve made rotationally fast with a member for mechanically operating the steering mechanism and with a resilient connecting device for rotary drive interposed between the steering shaft and the operating member and including a bar shaped as a connecting rod, the end of which that is opposite to that made rotationally fast with the operating member being connected to the steering shaft through a resilient coupling arrangement located outside of the assistance valve, the degree of assistance of which is selectively variable.

What is claimed is: 
     
       1. A power-assisted steering device for an automotive vehicle, comprising a power-assisted steering valve having a rotor rotatively coupled to a steering shaft of the vehicle,   a stationary body comprising a box including said rotor,   a tubular sleeve located within the box, coaxially surrounding said rotor and rotatively coupled to a steering mechanism operating member,   a connecting rod coaxially located within said valve and having an end located within said valve which is rotatively coupled to said operating member and an opposite end, and   a resilient coupling means interconnecting said steering shaft and said opposite end of said connecting rod for allowing said steering shaft to resiliently rotate with respect so said connecting rod.   
     
     
       2. A device according to claim 1, wherein said resilient coupling means comprises a stator member secured to said opposite end of said connecting rod,   a rotor member secured rotatably to said valve rotor and to said steering shaft, and   resilient connecting means mounted between said rotor and stator members of said coupling means and adapted to allow a resilient relative rotary movement between said stator and rotor members in order to allow a torsional flexibility of the connection therebetween.   
     
     
       3. A device according to claim 2, wherein said resilient coupling means allows a variation in the torsional flexibility of the connection between said rotor and stator members. 
     
     
       4. A device according to claim 3, wherein said rotor and said stator members are arranged coaxially and an annular space is formed between them, wherein said resilient connecting means comprises at least one spring means located within said annular space and secured by its ends to said rotor and said stator members respectively, and   at least one of said resilient coupling means being movable for varying the distance between said respective resilient coupling means in order to ensure said variation in flexibility.   
     
     
       5. The device of claim 4, wherein said resilient coupling means associated with said stator member are movable. 
     
     
       6. A device according to claim 3, wherein said resilient connecting means comprises at least one spring means having two ends and secured by its said two ends to said rotor and said stator members respectively, and   at least one of said resilient coupling means being movable for varying the distance between said respective resilient coupling means in order to ensure said variation and flexibility.   
     
     
       7. A device according to claim 1, wherein the end of said bar which is opposite to the end rotatably coupled to said operating member is mounted outside of said valve and carries said stator member of said resilient coupling means.